This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Heart Failure (HF) is a prevalent and growing cardiovascular disorder that utilizes a tremendous portion of healthcare resources. Current quantitative evaluation techniques are invasive and yield limited, one time information about HF, which itself is poorly understood. In both outpatient and inpatient settings, evaluation is limited to chest radiographs and physical assessment, which prior studies have shown to have poor accuracy in detecting HF severity and in guiding treatment. Recently developed noninvasive monitoring techniques and technologies are now available which in preliminary studies suggest the perfusion status of these patients is significantly reduced and impacted minimally by inpatient treatment. Our goal in this study is to use noninvasive monitoring techniques in the symptomatic hospitalized HF population to further define the relationship between tissue oxygen transport, patient symptoms, traditional physician assessment and treatment, as well as recidivism. Discharged inpatients and stable clinic patients will be serially reassessed to determine the behavior of oxygen transport and utilization over time. These values will be evaluated to determine if they approach those of the stable outpatient heart failure population. We hypothesize perfusion parameters and their rate of change during treatment and after discharge will be sensitive predictors of HF outcome and mortality. Specific Aims 1. To characterize global and tissue specific oxygen transport parameters in HF patients who are acutely symptomatic and more closely trend their responses to treatment. 2. To compare global and tissue specific oxygen transport parameters with the severity of patient symptoms and physician assessment. 3. To compare systemic and tissue specific oxygen transport parameters with 6 month rates of readmission and death rates after discharge from the ED or inpatient setting. 4. To compare systemic and tissue specific oxygen transport parameters with Doppler echocardiographic variables, lactate and BNP levels. 5. To measure systemic and tissue specific oxygen transport parameters during the first 4 weeks after hospitalized inpatients have been discharged and compare these values and trends of stable HF patients who will be reassessed over 3 months.